Electrical connectors which are designed for high current applications are made in a variety of configurations so that a male plug designed for one type of use will not be matable with a female receptacle intended for a significantly different use. For example, it should be physically impossible to connect a plug designed and approved for 125 volt use with a receptacle designed for use with, and possibly connected to, a 480 volt source. In the connectors known as locking connectors, which involve axial joining followed by a rotational locking movement, the blades of such connectors are necessarily on circular paths concentric with the centers of the connector halves.
A dominant line of connectors designed to satisfy these basic requirements and other safety and operating requirements has been on the market for several years. These connectors use several distinct blade designs in conjunction with a selection of arrangements of bumps and grooves on the mating connector parts to assure that the male and female connector halves cannot be joined unless they are specifically intended to be.
While the various permutations of these arrangements has performed their tasks well, the successful use of the connector portions also depends upon proper assembly of the components which form the connector halves and proper wiring of the connectors in the field. It has been customary to rely upon the skill and care of individuals involved in these steps but that has proved not always to be adequate and, in addition, the assembly of the connector halves has become quite expensive.
It has therefore become important to have a set of connectors which are compatible with the previously used connectors of the same types, for replacement purposes, but which are more economical to assembly and in which the components are reliably and unmistakably assembled in their proper relationships.